To manage cardiac disorders and irregularities it is useful to identify and characterize a patient's cardiac arrhythmia episodes. Conventionally, electrocardiogram (ECG) and intra-cardiac electrogram signals can be analyzed to detect and diagnose arrhythmia events. Conventional systems for cardiac arrhythmia identification and analysis utilize ECG data only and do not take into account hemodynamic changes that are in general considered by the clinical expert to access the patient state and determine whether there is a need for action (such as medication and catheter ablation) to reverse the adverse condition.
Early recognition of arrhythmias is an important contributor to manage cardiac disorders and irregularities. Currently cardiac arrhythmia monitoring and identification is based on waveform shapes and analysis of time domain parameters (e.g., P wave, QRS complex, ST segment, T wave, etc.). Proper arrhythmia identification and treatment using such conventional systems still require a systemic approach that incorporates vital signs such as arterial blood pressure, patient medical history including medications and surgeries, and demographics.
Other conventional systems also interpret electrophysiological signals using mathematical analysis (e.g., frequency analysis, symbolic complexity analysis and nonlinear entropy evaluation). Other existing approaches analyze signal characteristics (e.g., waveform amplitude, power spectrum, etc.), but might not be able to discern small changes in a portion of the cardiac cycle.
Prior methods to identify arrhythmia events can be based on hard-coded thresholds obtained by an understanding of the physiological system. These thresholds are from a limited group of patients. Threshold-based methods are widely adopted in industry due to ease of implementation on the bed-side. However, the threshold-based methods generate a lot of false alarms that may cause an unnecessary burden on nurses and clinicians result in alarm fatigue. Even when arrhythmia events are correctly identified, the impact of these events on the ability of the heart to properly perfuse the tissues in the body is not ubiquitously monitored.